Validity of the single-particle description and charge noise resilience for multielectron quantum dots

We construct an optimal set of single-particle states for few-electron quantum dots (QDs) using the method of natural orbitals (NOs). The NOs include also the effects of the Coulomb repulsion between electrons. We find that they agree well with the noniteracting orbitals for GaAs QDs of realistic parameters, while the Coulomb interactions only rescale the radius of the NOs compared to the noninteracting case. We use NOs to show that four-electron QDs are less susceptible to charge noise than their two-electron counterparts.Comment: 11+ pages, 5 figure

Hotel restaurant concept selection considerations: Which factors to take into account?

Hotels fulfill a variety of roles in our society. For many travelers and vacationers, a hotel is a home away from home. A wide range of social and meeting activities are held in a hotel such as weddings, meetings, tradeshows, conventions and family reunions. Hotels provide employment for many and support the local community through the collection of taxes such as sales, payroll and hotel. Various facilities and services can be offered or housed in a hotel such as guestrooms, meeting rooms, spa and fitness facilities, restaurants, bars, casinos, parking facilities and business centers. Depending on the location and function of a hotel, its facilities can be geared primarily towards hotel clientele only (for example in a resort in a remote location) or the hotel and its services can be marketed to a combination of hotel guests and local residents and consumers (individuals and businesses). The latter may be the case with a business hotel in downtown Manhattan for example. When a hotel operator follows a strategy of serving different market segments concurrently, he can be faced with difficult questions and decisions about how to develop, design and manage the hotel’s facilities and service offerings. Many decisions about the programming and development of a hotel will impact the hotel operation for many years to come and will therefore have a significant impact on the success potential of the hotel. Should a hotel have 10,000 or 15,000 square feet of meeting space? Should the hotel have one or two restaurants and what concepts should these restaurants be all about? With the role of hotel restaurants changing in the United States and an apparent need for hotel restaurants to become more competitive and distinct in the overall restaurant marketplace, ensuring that the appropriate restaurant concept is chosen for a hotel restaurant site is becoming more important. As the hotel restaurant marketplace is evolving, there may be an opportunity to identify and review which criteria a hotel owner or operator can consider in this hotel restaurant concept selection process. This will be done through a literature review of the restaurant concept selection and development process as well as the restaurant and retail site selection process. Following a description of the purpose of the paper including the research objective, its justification as well as the constraints of the project, the findings of the review of the literature will be presented. Conclusions will be discussed and recommendations will be made for hotel operators faced with the challenge of determining which concept to choose for a hotel restaurant project in the final part of this paper

One-second coherence for a single electron spin coupled to a multi-qubit nuclear-spin environment

Single electron spins coupled to multiple nuclear spins provide promising multi-qubit registers for quantum sensing and quantum networks. The obtainable level of control is determined by how well the electron spin can be selectively coupled to, and decoupled from, the surrounding nuclear spins. Here we realize a coherence time exceeding a second for a single electron spin through decoupling sequences tailored to its microscopic nuclear-spin environment. We first use the electron spin to probe the environment, which is accurately described by seven individual and six pairs of coupled carbon-13 spins. We develop initialization, control and readout of the carbon-13 pairs in order to directly reveal their atomic structure. We then exploit this knowledge to store quantum states for over a second by carefully avoiding unwanted interactions. These results provide a proof-of-principle for quantum sensing of complex multi-spin systems and an opportunity for multi-qubit quantum registers with long coherence times

The effect of a multidisciplinary outpatient team approach on outcomes in diabetic foot care:a single center study

BACKGROUND: Recent studies showed no reduction in major amputation rates after introduction of a multidisciplinary team (MDT) approach for the treatment of diabetic foot ulcer. The efficacy of MDTs in the current standard of care is being questioned. This retrospective single-center study evaluated the efficacy of an outpatient MDT approach on limb salvage and ulcer healing in treating diabetic foot ulcers.METHODS: Patients with a diabetic foot ulcer treated before (2015) and after (2017) implementation of an MDT in a single center were compared. The MDT met weekly and consisted of a vascular surgeon, physiatrist, internist, shoe technician, wound care nurse, nurse practitioner, cast technician, and podiatrist. The primary outcome was limb salvage at 1 year. Secondary outcomes were ulcer healing, amputation-free survival, freedom from any amputation, and overall survival. Multivariable Cox regression models were used to assess predictors for major amputation.RESULTS: A vascular surgeon treated 104 patients with 148 ulcers in 2015, and the multidisciplinary team treated 133 patients with 188 ulcers in 2017. Limb salvage (90.9% vs. 95.5%, P = 0.050), freedom from any amputation (56.5% vs. 78.0%, P &lt; 0.001), and ulcer healing (48.3% vs. 69.2%, P &lt; 0.001) were significantly lower in the non-MDT group than in the MDT group. Amputation-free survival and overall survival did not differ significantly between the groups. Predictors for major amputation were University of Texas Wound Classification 3D (hazard ratio, 2.8; 95% confidence interval, 1.17-6.45) and being treated in the non-MDT group (hazard ratio, 3.7; 95% confidence interval, 1.25-11.08).CONCLUSIONS: This retrospective study found an MDT dedicated to diabetic foot care was highly effective in increasing limb salvage and ulcer healing. We advise that such an MDT is an integrated part of the patient's chain-based care.</p

Heterogeneously Catalyzed Continuous-Flow Hydrogenation Using Segmented Flow in Capillary Columns

Segmented flow in standard GC capillary columns, with a heterogeneous Pd catalyst on the walls, gave rapid information about catalytic processes in them. The residence time and conversion was monitored visually, greatly simplifying bench-scale optimization. Examples show the benefits of the elimination of pore diffusion and axial dispersion. Further, we demonstrated how to quickly identify deactivating species in multistep synthesis without intermediate workup

Managing Successional Stage Heterogeneity to Maximize Landscape-Wide Biodiversity of Aquatic Vegetation in Ditch Networks

The presence of a high diversity of different successional stages in a landscape may help to conserve and promote landscape-wide biodiversity. A strategy to achieve this is using Cyclic Rejuvenation through Management (CRM), an approach employed in a variety of different ecosystems. CRM periodically resets the successional stages in a landscape. For aquatic systems this constitutes vegetation removal and dredging. For this approach to be useful (a) successional stages are required to be different in community composition and (b) these differences need to be caused by true replacement of species between stages. While potentially valid, these assumptions are not generally tested prior to application of CMR. In this study we test these assumptions to explore the usefulness of managing on successional stage heterogeneity for maximizing landscape-wide aquatic plant diversity. We carried out vegetation surveys in the ditch networks of 21 polder landscapes in Netherlands, each containing 24 ditch reaches. Using a clustering approach combined with insight from literature on vegetation succession in these systems we assigned our sampled communities to defined successional stages. After partitioning landscape diversity into its alpha and beta components, we quantified the relative importance of replacement among successional stages. Next, through scenario analyses based on simulations we studied the effects of reducing successional stage heterogeneity on landscape-wide biodiversity. Results showed that differences in community composition among successional stages were a potentially important factor contributing to landscape diversity. Early successional stages were characterized by higher replacement of species compared to late successional stages. In a scenario of gradual decrease of heterogeneity through the systematic loss of the earliest successional stages we found 20% of the species richness in a polder was lost, pointing toward the importance of maintaining early successional stages in a polder. This makes a compelling case for application of CRM within agricultural drainage ditch landscapes to maximize regional aquatic plant diversity. While applied to drainage ditch systems, our data-driven approach is broadly applicable to other systems and may help in providing first indications of the potential of the CRM approach. We argue that CRM may maintain and promote regional biodiversity without compromising the hydrological function of the systems